Although a retail package can be decorative and encourage purchase of the enclosed article, the primary purpose of any packaging is to protect the article from shipping and handling damage. Auxiliary packing forms and materials within the package also may have other functions, but again, the primary function is to protect the article from shipping and handling damage.
Packing materials and forms can be separated into 2 categories; (1) interface materials which directly contact the article being protected, and (2) structural materials which support and/or reinforce package and interface materials.
Interface and structural packing materials and forms should be small, light weight, pleasing in appearance and low in cost. However, at the same time, the packing must be able to withstand shipping and handling loads transmitted by the external package or container without transmitting excessive amounts of these loads to the article being protected. Interface and structural packing must also be able to perform it's functions within the limitations of a difficult environment, including extremes of temperature, altitude (pressure), shock, vibration, and stacking of containers and or articles within containers.